In this work reverse osmosis technology was used for removing alcohol from beer. The process was carried out in a diafiltration mode and it was possible to obtain a final beer with low ethanol content (less than 0.5% v/v). Several cellulose acetate and polyamide membranes were tested with transmembranar pressures ranging from 20 to 40 bar. Temperature and feed flowrate varied from 5 to 20 degrees C and from 2 to 71 center dot min(-1), respectively. It was observed that permeate flux and alcohols rejection increase with the feed pressure, whereas esters rejection decreases with pressure. Permeate flux increases with temperature, while rejections decrease with it. Concentration polarization occurs at low feed flowrates.